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QJEEM25Ch9683: JEE Main 2025 Chemistry - Class 12 JEEM25Ch9683 Solution: Given below is the plot of the molar conductivity vs for KCl in …

Given below is the plot of the molar conductivity vs  concentration \sqrt{\text { concentration }} for KCl in aqueous solution.

JEE Main 2025 (Online) 28th January Morning Shift Chemistry - Electrochemistry Question 1 English

If, for the higher concentration of KCl solution, the resistance of the conductivity cell is 100Ω100 \Omega , then the resistance of the same cell with the dilute solution is ' x ' Ω\Omega

The value of xx is _________ (Nearest integer)

Step-by-Step Verified Solution

amp;R=ρℓAamp;κ=G⋅G∗G=1R;κ=1ρamp;G∗=ℓAamp;R= Resistance amp;ρ= Resistivity amp;ℓA= cell constant⁡(G∗)amp;κcκd=RdRc;λm=κ×1000Camp;κcκd=(λm⋅C)(λm⋅C)d=RdRcc= concentrated sol. .d= diluted solution amp;100⋅(0.15)2150.(0.1)2=Rd100amp;Rd=150Ω\begin{aligned}& \mathrm{R}=\rho \frac{\ell}{\mathrm{A}} \\& \kappa=G \cdot G^* \quad G=\frac{1}{\mathrm{R}} ; \kappa=\frac{1}{\rho} \\& \mathrm{G}^*=\frac{\ell}{\mathrm{A}} \\& \mathrm{R}=\text { Resistance } \\& \rho=\text { Resistivity } \\& \frac{\ell}{\mathrm{A}}=\text { cell } \operatorname{constant}\left(\mathrm{G}^*\right) \\& \frac{\kappa_{\mathrm{c}}}{\kappa_{\mathrm{d}}}=\frac{\mathrm{R}_{\mathrm{d}}}{\mathrm{R}_{\mathrm{c}}} ; \lambda_{\mathrm{m}}=\frac{\kappa \times 1000}{\mathrm{C}} \\& \frac{\kappa_{\mathrm{c}}}{\kappa_{\mathrm{d}}}=\frac{\left(\lambda_{\mathrm{m}} \cdot \mathrm{C}\right)}{\left(\lambda_{\mathrm{m}} \cdot C\right)_{\mathrm{d}}}=\frac{\mathrm{R}_{\mathrm{d}}}{R_{\mathrm{c}}} \quad \begin{array}{l}\mathrm{c}=\text { concentrated sol. } . \\\mathrm{d}=\text { diluted solution }\end{array} \\& \frac{100 \cdot(0.15)^2}{150 .(0.1)^2}=\frac{\mathrm{R}_{\mathrm{d}}}{100} \\& \mathrm{R}_{\mathrm{d}}=150 \Omega\end{aligned}

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